1. Field of the Invention
The invention relates to a method and apparatus for monitoring the performance of an electric power distribution system, and in accordance with aspects of the invention, defining normal ranges unique to a specific system for selected parameters through the generation of statistically derived parameter thresholds.
2. Background Information
Numerous methods and systems have been developed to measure and capture power quality events in electric power distribution systems. However, the state of the art systems and methods lack the means for informing the user whether the existing power quality is normal. For example, power quality meters display and record values and minimum and maximum extremes, but even if a parameter is within the prescribed range, it does not necessarily follow that all is well. Furthermore, attempts to predefine acceptable power quality levels fails to acknowledge unique attributes of a particular site in an electrical system. In one computer implemented system, the triggers are dynamically adjusted to achieve a desired rate of events. In practice, the method results in bursts of events that are not very extraordinary as the threshold is set just above nominal and is therefore, very sensitive. Furthermore, the user is still not aware of whether the conditions are normal even though the parameters may be within the dynamically adjusted ranges.